Oh yeah, it’s on: welcome to the party, Windows Phone 7 Series.

Today marks a sea change in Microsoft’s mobile device strategy and how we are going to market in the smartphone space. This change is fundamental rather than incremental; we have completely re-written the book on how a Windows Phone looks, behaves and interacts with a user. With the MIX10 opening keynote (you can watch the on-demand video here), we introduced the details on how designers and developers can create incredible and immersive solutions for Windows Phone 7 Series.

I don’t think I can stress how different this new offering is to not only our previous smartphone offerings, but also how different Windows Phone 7 Series is compared to the most popular smartphone competitors on the market today. In making the user central to the experience, the Windows Phone 7 Series product team has created a product that is productive, focused and fun to use.

Some of the things we have announced are:

A consistent experience across devices

All Windows Phone 7 Series devices will share a common screen resolution and hardware specifications

An intuitive, delightful and fresh User Interface

Adoption of the code name “Metro” user interface which was derived from the highly acclaimed UI in the Zune HD media player

Tiles: launch points for phone functionality on the home screen that also share contextual and relevant information important to the user

The fact that the application model leverages Silverlight and XNA is significant in that you can reuse your skillsets that you have acquired building regular Silverlight apps and XNA-enabled games. This means that if you have built Silverlight applications or XNA games in the past, you’ll find the application creation process very familiar and will allow you to hit the ground running.

Below are some helpful resource links that you can use to learn more about Windows Phone 7 Series application development and actually start building your apps right now: